{"ob_id":65513,"names":[],"terms":[{"ob_id":64470,"label":"units","value":"","vocabulary":""},{"ob_id":67845,"label":"var_id","value":"20","vocabulary":""},{"ob_id":69247,"label":"long_name","value":"As ","vocabulary":""},{"ob_id":69282,"label":"standard_name","value":"the concentration of water soluble As in PM2.5","vocabulary":""}]}